Air Pollution, High-Fat Diet Cause Atherosclerosis in Laboratory Mice
Test results with laboratory mice show a direct cause-and-effect link between exposure to fine particle air pollution and development of atherosclerosis, commonly known as hardening of the arteries.
Mice that were fed a high-fat diet and exposed to air with fine particles had 1.5 more times plaque production than mice fed the same diet and exposed to clean air. Plaque, a fatty deposit on the inner lining of the blood vessels, can predispose individuals to conditions such as heart attacks and strokes. The fine particle exposure also led to increased inflammation of the artery walls and reduced function of the artery wall’s inner lining.
The findings of the study may explain why people who live in polluted areas have a higher risk of heart disease. The findings are also important because the fine particle concentrations used in the study were well within the range of concentrations found in the air in the Northeastern U.S.. The average particle concentration over the course of the study was below the current 24-hour standard of 65 µg/m3 and close to the annual average standard of 15 µg/m3.
“These results suggest that repeated periods of short-term (eg, several hours) exposures to high particulate matter levels, such that may occur during rush hour traffic, is potentially capable of promoting progression of atherosclerosis, although the mean daytime particulate matter exposure concentration is within national recommendations. This may potentially have implications for the relevance of both the 24-hour and annual average National Ambient Air Quality Standards,” concluded the study authors.
Sun Q, Wang A, Jin X, Natanzon A, Duquaine D, Brook RD, Aguinaldo J-GS, Fayad ZA, Fuser V, Lippmann M, Chen LC, Rajagopalan S. Long-term Air Pollution Exposure and Acceleration of Atherosclerosis and Vascular Inflammation in an Animal Model. JAMA 2005; 294: 3003-3010.
For a copy of the abstract click here.
